A Theoretical Calculation Method of the Unsupported Span for the Shallow Tunnel in the Soft Stratum

<div>A calculation model of the unsupported span. (a) Three-dimensional model. (b) Failure mode of the arch crown. (c) Failure mode of the tunnel face.</div>

Advances in Civil Engineering

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Figure 3

Figure 3: A Theoretical Calculation Method of the Unsupported Span for the Shallow Tunnel in the Soft Stratum 